Biomass and eco- friendly additives blends for steel protection in acidic media: experimental and computational study
Date
2023-08
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Federal University of Technology, Owerri
Abstract
The blends of ethanol extract of Pterocarpus santalinoides, PS (Nturukpa leaves), Piper guineense, PG (Uziza seeds), Picrilima nitida, PN (Akuama leaves) and potassium iodide, KI and sodium alginate, SA respectively were investigated as green corrosion inhibitors for the protection of mild steel in 0.5 M HCl and 0.25 M H2SO4 using experimental and computational approach. Results of gravimetric technique revealed corrosion inhibition efficiency (IE) of 63 % and 43 % at 120 h for mild steel in the presence of 1000 mg/L of PS concentration in 0.5 M HCl and 0.25 M H2SO4 respectively, 81 % and 86 % at 120 h for mild steel in the presence of 1000 mg/L of PG concentration in 0.5 M HCl and 0.25 M H2SO4 respectively, 77 % and 64 % at 120 h for mild steel in the presence of 1000 mg/L of PN concentration in 0.5 M HCl and 0.25 M H2SO4 respectively. progressively the corrosion inhibitor formed by optimal combination of PS, KI, and SA exhibited IE of 97 % at 120 h at room temperature in 0.25 M H2SO4. In addition, characterization studies done on the extracts using GC-MS and UV-Vis equipment revealed the phytochemical constituent’s presence in the extracts, some were selected for theoretical computations based on their abundance. Furthermore, the density functional theory (DFT) calculations revealed the chemical indicators responsible for the adsorption and inhibition process within the inhibitor molecules and the binding energy of interaction (that is, adsorption strength) between the inhibitive molecules and Fe crystal (1 1 0) surface. FTIR spectra analysis revealed the possibility of adsorption and interaction of active elements heteroatoms on the mild steel surface. The Langmuir adsorption isotherm was also obeyed. Conclusively, SI shows a cooperative synergistic effect as the SI values are above unity.
Description
A Master's thesis in Corrosion Technology.
Keywords
Ethanol extract, blends, inhibitor, corrosion, density functional theory, corrosion technology
Citation
Eziuka, J. E. ( 2023). Biomass and eco-friendly additives blends for steel protection in acidic media: experimental and computational study. (Unpublished master thesis), Federal University of Technology, Owerri.